Study of damping effect of the floodwater on a damaged ship roll motion

Roll decay of a ship in flooded condition was studied experimentally and numerically. Two different flooded compartment layouts were used. Floodwater motions in the compartments were simulated numerically by applying lumped mass with a moving free surface method. Water exchange through the non-watertight bulkheads in compartment was modeled by applying hydraulic equation. Free roll decay in the undivided compartment was non-harmonic, both in terms of amplitude and roll period. Divided compartment roll decayed significantly faster in flooded compartment. Numerical method was showed to be capable of predicting the roll decay in flooded condition.